National Instruments PCI-6023E - Manual (Page 59)

Chapter 4 Signal Connections
PCI-6023E/6024E/6025E User Manual 4-30 © National Instruments Corporation
Power Connections
Two pins on the I/0 connector supply +5 V from the computer power
supply via a self-resetting fuse. The fuse will reset automatically within a
few seconds after the overcurrent condition is removed. These pins are
referenced to DGND and can be used to power external digital circuitry.
• Power rating +4.65 to +5.25 VDC at 1 A
Caution Under no circumstances should you connect these +5 V power pins directly to
analog or digital ground or to any other voltage source on the board or any other
device. Doing so can damage the board and the computer. National Instruments
is
NOT liable for damages resulting from such a connection.
Timing Connections
Caution Exceeding the maximum input voltage ratings, which are listed in Table 4-2, can
damage the board and the computer. National Instruments is
NOT liable for any
damages resulting from such signal connections.
All external control over the timing of your board is routed through the 10
programmable function inputs labeled PFI<0..9>. These signals are
explained in detail in the section,
Programmable Function Input
Connections . These PFIs are bidirectional; as outputs they are not
programmable and reflect the state of many DAQ, waveform generation,
and general-purpose timing signals. There are five other dedicated outputs
for the remainder of the timing signals. As inputs, the PFI signals are
programmable and can control any DAQ, waveform generation, and
general-purpose timing signals.
The DAQ signals are explained in the DAQ Timing Connections section
later in this chapter. The waveform generation signals are explained in the
Waveform Generation Timing Connections section later in this chapter.
The general-purpose timing signals are explained in the General-Purpose
Timing Signal Connections section in this chapter.
All digital timing connections are referenced to DGND. This reference
is demonstrated in Figure 4-16, which shows how to connect an external
TRIG1 source and an external CONVERT* source to two PCI E Series
board PFI pins.
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PCI.book Page 30 Wednesday, September 16, 1998 9:09 AM